Re: confused
It's down to accounting,
Cloud services are expenses, and thus can be directly offset agains this year's earnings.
Buying servers is capital expenditure which can only be offset as depreciation, and that takes several years.
In the meantime, you have staffing costs (and if your workload only needs half the time of an expert admin, you'll find you've either got to hire the full time of that expert, or make do with an inexpert admin), maintenance and repairs.
Servers are now a vital infrastructure for pretty much any kind of business, whether it be in the technology field or not. Companies no longer build their own offices*, so why build their own IT infrastructure?
None of this applies to businesses whose business is technology, but even then, cloud-hosting is a low-risk way to protoype or trial new products and services - if the idea isn't a goer, you're not left with a pile of servers you don't have a use for.
(* Yes, yes, Apple, donut, folly, overrun, moneypit)
Biting the hand that feeds IT
